Communication equipment



April 1941- J. o. HARVEY 2,239,094

COMMUNICATION EQUIPMENT Filed May 2'7, 1938 2 Sheets-Sheet 1 Inventor UQM 0.

April 1941- J. 0. HARVEY 2,239,094

COMMUNICATION EQUIPMENT Filed May 27, 1938 2 Sheets-Sheet 2 Inventor W Patented Apr. 22, 1941 UNITED STATES PATENT ()FFICE 8 Claims.

My invention relates to automatic telegraphic mechanisms for transmitting the readings or indications of instruments from a remote point at predetermined intervals or at will.

he primary object of this invention is to provide a means whereby the numerical registrations of meters, gauges, recorders, etc., can be transmitted either by radio or by direct wire, and to provide also a means whereby the source of this information can be readily identified.

The invention is particularly adapted to the transmission of mensural data concerning water levels, flood control, and various meteorological conditions, and it is designed to operate over The telegraphic mechanism of this invention would ordinarily operate in conjunction with a control clock, and a small radio transmitter, all of which could be incorporated into a single unit if so desired. In this case, the control, or

master clock would be provided with two sets of electrical contacts operating simultaneously, one for energizing the radio transmitter filament circuit, and the other for energizing the circuit of the motor driving the telegraphic mechanism. The control clock contacts would also open simultaneously at the end of any predetermined operating period during which time a series of signals would be transmitted. From the foregoing description it will be clear that no appreciable burden is placed upon the control clock since it operates as a master only, and assumes no part of the burden imposed upon the driving motor. This feature insures the accurate timing of the transmission interval.

The invention would not be limited, however, to radio operation since it is equally well adapted to direct wire or carrier current service, in which case the control clock would not be necessary, as a signal could be obtained and controlled as desired from the receiving end. In this case all V that would be necessary would be suitable switching equipment at the receiving end tor starting and stopping the driving motor. This, however, would constitute no part of the invention.

Considered broadly, the telegraphic mechanism in one form of this invention comprises a plurality of radial cams, connected together with intermittent gears, a separate cam being used for each order of digits, as for example, units, tenths, hundrfidths, etc. This system of cams is rotatable in either direction and is actuated in response to the rise or fall of any variable magnitude that can be translated into mechanical efiort, such as pressure, temperature, velocity, etc. Partially encircling the radial cams, by varying amounts and forming an integral part thereof, embossed annular rings, or portions thereof, preferably nine in number, are spaced at regular intervals, the central ring forming a complete circle. Operating in conjunction with each radial cam and revolving in the circle of which, each cam forms a part, normally open electrical co-ntactors are caused to close momentarily in response to the number of embossed surfaces on the cam with which they make mechanical engagement. This momentary closing of ,the contacts produces dots and dashes as known in telegraphic parlance. One dot represents the digit one, two dots represent the digit two, etc., and zero is represented by a long dash corresponding to a long horizontal bar on the radial cam. One pair of electrical contactors is provided for each radial cam and all are connected inpparallel. These electrical contactors are carried upon a common shaft and the angular displacement between each is such that no two can operate simultaneously.

In order that each installation may be clearly identified, it becomes necessary to transmit with numerical signals, what might be termed the station identification code, which would consist of letters rather than numbers. This is accomplished by means of an adjustable code plate on which dots and dashes corresponding to the letters of the code are cut as teeth upon a circular are having the same radius that was used in the forming of the radial cams. serves also to punctuate the numerical signal, since one of the rotating contactors above referred to is caused to engage with the teeth of the code plate immediately ahead of the radial cam corresponding to the units place in the indication. The numerical signal transmitted immediately following the code will therefore be the first digit in the reading. The next will be the second digit, etc., until a cycle has been completed. Between the code and each successive signal a certain elapsed time interval makes the reading intelligible.

In terms of greater detail, the form of the invention illustrated in Figures 1 to 4 inclusive, comprises a base plate I, supporting the vertical standards 2, which are held rigidly by means of the spacer bars 3.

By means of a flexible cable 5, the vertical motion of a float 4, corresponding to various liquid levels, is transmitted to the pulley 6, which is keyed or otherwise connected to the shaft 1. A counterweight is used on one end of cable 5, although it is not shown on the drawings. Spur gear 8 is also keyed to the same shaft and therefore rotates with the pulley 6. In mesh with the spur gear 8 is the pinion 9 which is keyed to the shaft Iii. The transfer gears [3 are of the well known type commonly used in odometers and various counting mechanisms. Each transfer gear 63 is keyed to its respective shaft, Iii, H, or IE. The pinions M transmit the movements of the gears It.

The radial cams it are keyed or otherwise secured to the shafts H], H, and 32. For convenience, the circumference of the pulley 6 is assumed to be exactly one foot. It could be any other unit of measurement, however. For convenience also, the gear ratio between 8 and 9 is assumed to be 1:10. One complete revolution of 6 will therefore cause the shaft l2 to move revolution. The odometer wheel or gear on this shaft will then indicate an increase or decrease, as the case may be, of one unit. The complete reading of the instrument as shown in Figure 2 would accordingly be 5.14 feet.

The periphery of the radial cam I is divided into ten equal divisions of 36 degrees each, which correspond to the ten equal divisions on the periphery of the odometer wheel 13, one division being provided for each of the numbers from zero to nine inclusive.

Portions of the nine embossed annular rings which are equally spaced upon the radial surfaces of the cam is are cut away in amounts differing by 36 degrees each, or 1% revolution. Assuming an arbitrary starting point on the periphery of the cam It, the first 36 degree division is occupied by the zero bar 33. Adjoining this bar and continuous about the cam is the embossed ring corresponding to the digit one. The next adjacent partial ring would span an arc of 360 degrees'72 degrees or 288 degrees, and would correspond to the digit two, and the next partial ring corresponding to the digit three would diminish by 36 degrees and would therefore span an arc of 252 degrees etc., until finally the partial ring corresponding to the digit nine would span an arc of 36 degrees. These partial rings alternate from one side to the other with respect to the central ring. This feature tends to equalize the time interval between the various numbers when a signal is transmitted.

With reference again to the Figures 2 and 3, the vertical shaft 22 will be caused to rotate during a transmission interval by means of the driving motor I! which is connected thereto thru the pinion N3, the spur gear IS, the shaft 26, and the bevel gears 2|. This will cause the electrical contactors 23 to rotate with the shaft 22, thus closing and opening them in response totheir mechanical contact wtih the embossed rings on the pose and the retarding effect which it encounters in passing over the cam rings causes it to lag and to close the electrical contacts momentarily. The spring tension in the blades will cause them to open when they have passed over the ring. This feature is clearly shown in Figure 1. If the closed interval is brief, a dot will be indicated in the external circuit, while if the interval is prolonged a dash will be indicated. In precisely the same manner the dots and dashes of the identification code are produced when a contactor engages with the properly spaced teeth on the radial edge of the code plate 28. The radial cams I6 are secured upon their respective shafts in proper relationship to the numbers on the odometer wheels l3. For instance in the positions shown in Figure 3 the lower contactor 23 in its rotation would contact five rings on 16 and would therefore produce five dots indicating the digit five. The middle contactor 23 would likewise contact one ring, indicating the digit one, and in the same way, the upper contactor 23 would contact four rings on IS thus producing four dots indicating the digit four. The complete reading would therefore be 5.14, as indicated in Figure 2. Zero is represented by a long dash and is produced when any one of the contactors 23 engage with the zero bars 33.

To avoid confusion on the drawings the electrical cOnnections have been omitted on the Figures 1, 2, and 3, but are clearly shown, however, on the connection diagram, Figure 4. This diagram indicates that when the contacts 41 and 48 of the control clock 56 are closed, the mechanism will become operative. The circuit of the driving motor I! can be traced from battery 53 thru 48, thru motor I! and returning to 53 thru the grounded frame of the machine. The opening of contacts 46 at the end of an operating period will not cause the motor to stop instantly, because contacts 48 are shunted by contacts 26 until the cam 21 of the full-cycle switch returns to a point at which 26 will open. This arrangement prevents an interruption of the signal before it has been completed.

From the battery 52 the signal circuit can be traced thru relay 49, thru brush 25, collector ring 24, and returning to 52 thru any one of the parallel connected contactors 23, since one side of each is grounded to the shaft 22. In reality, but one collector ring 24 and one brush 25 (as shown in Figure 3), is used in the signal circuit. For schematic illustration, however, the convention followed in Figure 4 indicates the operation more clearly. The B battery 50 operates the plate circuit of the radio transmitter 54 thru relay 49. The filament circuit of battery 5| is completed thru the control clock contacts 41 which close simultaneously with 48. Terminals 3! are for the electrical connections.

Figures 5 and 6 represent a plan view with contacts removed, and a sectional elevation upon the line 46-46, of an alternate method for operating a single pair of electrical contacts 35 from one or more radial cams I6. The method illustrated dispenses entirely with the brush 25, collector ring 24 and the plurality of electrical contactors 23, shown in Figures 1, 2, and 3. The operation is accomplished in the method illustrated by means of one or more mechanical fingers 36 carried upon and rotating with a common tubular shaft 38.

The angular displacement between these fingers is similar to that shown for contactors 23 in Figure 4. Whenthe finger 36, which is pivoted upon the yoke 31, rotates with the shaft 38, the motion imparted to the finger 36 by its mechanical engagement with the embossed surfaces upon the cam I5 is transferred to the bell crank 40 which in turn raises the push rod 4| by means of the collar 42 thus closing the electrical contacts 35. The travel of the push rod is limited by means of the lock nuts 45, and the rod is guided by the sleeve 44. The tubular shaft 38 rotates within the bearing 43 and the pivot block 33 rotates with 38 and upports the bell crank 40.

Altho Figures 5 and 6 indicate the operation of only one radial cam 16, it will be clear that the push rod 4| is operable by any one of a plurality of cams l6 thru mechanical means identical with that shown.

The electrical connections to a signal circuit are indicated at 55. The application to such a circuit would be identical with the method illustrated in Figure 4.

I claim:

1. In a. telegraphic apparatus for transmitting mensural data, a measuring mechanism including a device having a plurality of mechanical actuators of different denominational values each provided with relatively spaced actuating means of progressively diiferent actuating values, said actuators being movable in response to variations in the quantity to be measured to bring to effective positions the actuating means comparable in value to the measured quantity, a separate keying e switch for each of said actuators normally posi tioned out of engagement with the respective actuators and at successively increasing distances therefrom, drive means for translating said keying switches through a predetermined operating cycle to successively engage and be actuated by the eiTectively positioned actuating means of its associated actuator.

2. An actuator for opening and closing a registering circuit in accordance with a prevailing changeable condition, comprising a cylinder-like body having a plurality of axially spaced circuit actuating ribs terminating in a surface of revolution obtained by revolving a concave are about the axis of said body, said ribs differing in extent with respect to each other, with one end of each rib in substantial alignment with the corresponding end of each of the other ribs.

3. An actuator for opening and closing a registering circuit in accordance with a prevailing changeable condition, comprising a rotatable body having a plurality of spaced contact establishing ribs disposed on the surface of said body in the direction of rotation thereof, with those ribs to one side of a median division line successively varying in extent of encirclement of said body while those to the other side of said division line similarly vary but alternate as to such extent with those of the first group.

4. An actuator for opening and closing a registering circuit in accordance with a prevailing changeable condition, comprising a rotatable cylinder-like body having a plurality of spaced contact establishing ribs, each disposed on the longitudinal surface of said body in the direction of rotation thereof, with those ribs to one side of a median plane between the ends of said body, successively varying in extent of encirclement of said body while those to the other side of said median plane similarly vary but alternate as to such extent with those of the first group.

5. In apparatus for electrically registering a prevailing changeable condition, a plurality of rotatable electrical contact actuators supported with their axes in a common plane, each of said contact actuators having contact establishing elements adapted to function in accordance with the rotative position of said actuator, means for coordinating the rotational velocities of said actuators in response to changes in said prevailing changeable condition to provide a set-up of said contact establishing elements indicative of the prevailing condition, separate contact means associated with each of said contact actuators and adapted to traverse the same, and means for causing said separate contact means to sequentially engage their associated actuators to electrically register such condition.

6. In apparatus for electrically registering a prevailing changeable condition, a plurality of rotatable electrical contact actuators supported with their axes in a common plane, each of said contact actuators having contact establishing elements adapted to function in accordance With the rotative position of said actuator, an indicia wheel associated with each actuator and mounted for rotation therewith to provide a visual indication of the functioning position of its associated actuator, and means for coordinating the rotational velocities of said actuators and indicia wheels in response to changes in said prevailing changeable condition to provide a visual registration of the prevailing condition as electrically registered by said contact actuators.

7. In apparatus for electrically registering a prevailing changeable condition, an actuator for opening and closing a registering circuit in accordance with such condition comprising a cylinder-like body having a plurality of axially spaced circuit actuating means terminating in a surface of revolution obtained by revolving a con cave are about the axis of said body, contact means adapted to swing along an arcuate path including said arc in a plane passing through the axis of said body, and a plate lying in said plane and having an arcuate edge coinciding with the path of travel of said contact means, said edge being notched to provide station identifying code symbols.

8. In apparatus for electrically transmitting information as to a prevailing changeable condition, means for setting up a series of contact actuating elements in accordance with changes in such condition, an impulse circuit including a movable contactor adapted to traverse said contact actuating elements to create corresponding impulses in said circuit, said contactor being normally out of contact with and spaced from said contact actuating elements to create a time interval before establishing engagement with any of said contact actuating elements to create such impulses, a transmitter having a normally open filament circuit and an anode circuit, means for simultaneously closing said filament circuit and initiating movement of said movable contactor, and means in said impulse circuit for keying said anode circuit in response to impulses developed in said impulse circuit following said time interval.

JAMES O-. HARVEY. 

